1. Field of the Invention
The present invention relates to novel polynucleotides encoding proteins involved in one-carbon compounds metabolism, derived from microorganisms belonging to methylotrophic bacteria and fragments thereof, polypeptides encoded by the polynucleotides and fragments thereof, polynucleotide arrays comprising the polynucleotides and fragments thereof
2. Discussion of the Background
Amino acids such as L-lysine, L-glutamic acid, L-threonine, L-leucine, L-isoleucine, L-valine and L-phenylalanine are industrially produced by fermentation by using microorganisms that belong to the genus Brevibacterium, Corynebacterium, Bacillus, Escherichia, Streptomyces, Pseudomonas, Arthrobacter, Serratia, Penicillium, Candida or the like. In order to improve the productivity of amino acids, strains isolated from nature or artificial mutants thereof have been used as these microorganisms, various techniques have been disclosed for enhancing activities of L-amino acid biosynthetic enzymes by using recombinant DNA techniques, to increase the L-amino acid-producing ability.
Productivity of L-amino acids has been considerably increased by breeding of microorganisms such as those mentioned above and the improvement of production methods. However, in order to meet further increase in the demand in future, development of methods for more efficiently producing L-amino acids at lower cost have still been desired.
As methods for producing amino acids by fermentation of methanol which is a fermentation raw material available in a large amount at a low cost, there have conventionally known methods using Achromobacter or Pseudomonas microorganisms (Japanese Patent Publication (Kokoku) No. 45-25273/1970), Protaminobacter microorganisms (Japanese Patent Application Laid-open (Kokai) No. 49-125590/1974), Protaminobacter or Methanomonas microorganisms (Japanese Patent Application Laid-open (Kokai) No. 50-25790/1975), Microcyclus microorganisms (Japanese Patent Application Laid-open (Kokai) No. 52-18886/1977), Methylobacillus microorganisms (Japanese Patent Application Laid-open (Kokai) No. 4-91793/1992), Bacillus microorganisms (Japanese Patent Application Laid-open (Kokai) No. 3-505284/1991) and others.
However, no methods have been described for producing L-amino acids using Methylophilus bacteria. Although methods described in EP 0 035 831 A, EP 0 037 273 A and EP 0 066 994 A have been described as methods for transforming Methylophilus bacteria using recombinant DNA, applying recombinant DNA techniques to improvement of amino acid productivity of Methylophilus bacteria has not been described.
Therefore, prior to the present invention genes isolated from Methylophilus bacteria that are involved in C1 assimilation and which can be used to improve the yield of amino acids in cultured microorganisms were not described.